Human brain activity is key in deception research

This article appears in the newest edition of Breakthrough Magazine, a publication that focuses on research and economic development at the University of South Carolina.

In the Fox Network TV show Lie to Me, Dr. Cal Lightman and his intrepid team figure out who is lying by spotting subtle body language cues and using their nifty Facial Action Coding System to detect microexpressions.

Twitch your eyebrows or tighten your jaw in front of those guys, and you're dead meat. They always catch the liars.

In real life, detecting deception isn't so easy. Real experts on deception will tell you that microexpressions and body language make for entertaining TV scripts but haven't been objectively verified for lie detection purposes. Even polygraph tests, though their track record is far more extensive, aren't admissible in court.

Jennifer Vendemia

It turns out the real answer to detecting deception is to search -- not in the black heart of deceit -- but in the neurological wiring of the human mind. That's what Carolina psychology professor Jennifer Vendemia has been doing for several years, and her research, currently funded with $5.1 million from several federal agencies, has turned up some interesting facts.

"We're mapping out the areas of the brain that are involved in deception," Vendemia said, "and looking for the precise brain-wave activity that occurs at the moment a person decides to deceive."

In more than six years of deception studies at the University of South Carolina, Vendemia's research group has been able to isolate, by analyzing brain waveforms of volunteer subjects, the exact instant when a person decides to lie. It's a fleeting moment-only a half-second long-that occurs just after a question is asked by an interrogator and before the subject's verbal response.

"What we're finding is that there is no naughty spot in the brain where the decision to tell a lie originates," Vendemia said. "There are multiple regions, and it's very individualized how each person's brain works.

"What's common for all of us, though, is that lying involves a decision. In the space of 800 milliseconds or so, we decide to inhibit a truthful response and give a deceptive response to a question."